Depth of planting req'd to successfully establish portugese laurel & coming up against concrete at 8 inches depth

[Suks13]

Hello,

I'm hoping someone could help with this query. I'm planting ready grown/rootball (125cm high) portugese laurel hedging along the side of my house. On digging the trench i have quickly come up against concrete & hardcore under the grass verge at about 8 inches.

I'm wondering if 8inches will be sufficient for the hedge to survive & also what adverse effect the concrete underneath the hedge will have?

Any advice much appreciated!

 

[cpp gardener]

That is about 28” too shallow. There is not enough root depth for the plants to be stable. Unless you can build a raised planter for them, you’ll need to build a fence.